Viewing archive of Wednesday, 28 September 2016

Daily bulletin on solar and geomagnetic activity from the SIDC

Issued: 2016 Sep 28 1230 UTC

SIDC Forecast

Valid from 1230 UTC, 28 Sep 2016 until 30 Sep 2016
Solar flares

Quiet conditions (<50% probability of C-class flares)

Geomagnetism

Minor storm expected (A>=30 or K=5)

Solar protons

Quiet

10cm fluxAp
28 Sep 2016085049
29 Sep 2016081030
30 Sep 2016078011

Bulletin

Solar activity is very low with only B-class flares reported. We expect solar activity to be low with possible, but not very probable, isolated C-class flare from the only active region observed on the visible side of the solar disc, NOAA AR 2597. No Earth directed CMEs were observed in the last 24 hours. The Earth is presently inside the fast solar wind with the speed of about 660 km/s (the peak value of 740 km/s was reached early this morning), and the interplanetary magnetic field magnitude is about 7 nT. The arrival of the fast solar wind from the coronal hole in the northern hemisphere with a low latitude extension (possibly also connected to the coronal hole on the southern hemisphere) has induced disturbed geomagnetic conditions in the evening of September 27 and early morning of September 28. The combination of the fast solar wind speed (about 600 km/s) and the intervals of the negative value of the Bz component of the interplanetary magnetic field (down to -9 nT), has caused the moderate storm conditions. The Potsdam station reported up to K=6, and NOAA reported Kp=6. We expect disturbed geomagnetic conditions to continue in the coming hours.

Today's estimated international sunspot number (ISN): 032, based on 20 stations.

Solar indices for 27 Sep 2016

Wolf number Catania036
10cm solar flux086
AK Chambon La Forêt051
AK Wingst036
Estimated Ap039
Estimated international sunspot number025 - Based on 33 stations

Noticeable events summary

DayBeginMaxEndLocStrengthOP10cmCatania/NOAARadio burst types
None

Provided by the Solar Influences Data analysis Center© - SIDC - Processed by SpaceWeatherLive

All times in UTC

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